Compensating clock-pendululvi



(No Model.)

. J. W. HILE. Compensating Clock Pendulum. No. 231,800. Patented Aug. 31,1880.

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WITNESSES v ATTORNEYS.

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UNITED STATES PATENT OFFICE.

'COMPENSATING CLOCK-PENDULUM.

SPECIFICATION forming part of Letters Patent No. 231,800,

dated August 81, 1880.

Application filed June 1, 1880. (No model.)

To all whom it may concern Be it known that I, JOHNW. HILE, of Leavenworth, in the county of Leavenworth and State of Kansas, have invented a new and Improved Olock-Pendulum and I do hereby declare that the following is a full, clear, and exact description of the same.

My invention is an improvement in the class of pendulums designed for use in connection with clocks requiringcom pensatin g-pendulu m. It is more particularly an improvement in that class of compensating-pendulums which are constructed of wooden and metal bars.

My improvement consists in the construction and arrangement of parts, as hereinafter described, whereby the bob or weight is adjusted up or down automatically to compensate for changes in the length or extension of the pendulum due to changes in temperature of the surrounding air or adjacent surfaces or objects.

In accompanying drawings, forming this specification, Figure 1 is a front view of the pendulum. Fig.2 is a like view, with part broken away, of apendulum constructed in a modified way. Fig. 3 is a vertical section on line as m, Fig. 1. Fig. 4 represents a modification.

The body or main portion A of the pendulum is constructed of wood, which substance has little or no appreciable lengthwise expansion under varying temperatures. The upper end of bar A is attached at a to a flat metallic bar, B, whose cylindrical upper. end is screwed into a nut, (J, whose rotation adjusts the pendulum higher or lower, as required, to regulate its Vibrations. The center of oscillation is at I), where the nut O rests on a fixed bar (not shown) that supports the pendulum. The bob or metallic weight D slides on the bar A, and is adjusted higher or lower by means of certain attachments, which I will proceed to describe.

The screw E is screwed through a metallic cap or end piece, 0, affixed to the end of the bar A, which, as shown in Figs. 2, 3, is slotted longitudinally. A short cross-bar, d, is swiveled to the upper end of the screw E, and projects laterally from the sides of the bar A, so as to enter grooves e in the bob D and engage the shoulders at the upper end of the same.

part of In Fig. at I show a modified construction. the end of the bar A not being slotted and the screw E entering the same and passing through the bend or middle portion of a U- shaped bar, F, whose arms are parallel and close to the sides of bar A, so as to liein the aforesaid grooves c.

The wooden bar A has no appreciable expansion or contraction, and may therefore be regarded as a negative element in this relation. The metallic barB and screw E, on the other hand, contract and expand readily under varying temperatures; but, owing to their relative location and the connection of the screw with the weight D, their variations in length are compensatory, so that the center of gravity of the pendulum, and hence its "ariations in given times, remains unchanged. Forexample, suppose the temperature becomes lower, the bar B will be shortened, which will raise and shorten the pendulum as a whole; but at the same time the screw E will contract to the same extent as bar B, and since the weightD is supported by said screw it will slide down on the bar A a distance equal to the contraction of the screw E, and the length of the latter above its point of attachment 0 to the pendulum-bar A being the same as that part of barB embraced between its point of attachment 1) to the bar A and the nut C, it is obvious the contraction of one, E, equals the other, 13, so that the center of gravity or aggregate weight of the pendulum is lowered to compensate for its contraction in length. If, on the other hand, the temperature rises, the expansion of bar D relative to the center of motion will lower the pendulum as a whole, while the like and simultaneous increase in the length of screw E will raise the weight D correspondingly, and thus cause the center of gravity to remain unchanged, so that the vibrations of the pendulum will be equal at all times.

As a means of adjusting the pendulum to time or changing its length to increase or diminish its rapidity of vibration, I may divide the bar transversely near the middle, as shown in Fig. 2, and thus form two parts, which I connect by one or more wood screws, F, whose adjustment will lengthen or shorten the bar.

In order to prevent one part of the divided bar turning (when but one screw is used on) independently of the other, and yet allow the desired lengthwise adjustment, I provide straight parallel guide-bars f, which are attached to the contiguous ends of the respective parts and slide in keepers or eyes g, fixed on the opposite parts of the bar.

The metallic cap or end piece 0 and screw E may be left out entirely, and the bob or ball D may rest its weight on a metallic bar shaped in the form of aT and affixed to the wood bar A by means of a pin passing through the latter and through the lower end of the T, to take the place of piece 0 and screw 1*], in which case the pendulum may be adjusted to temperature by turning nut G at the top and regulated to time by turning wood screw F, or else by adjusting-nut O, or the cylindrical upper end of fiat metallic bar B may be left out and the pendulum may be supported in the ordinary way, in which case the pendulum may be adjusted to temperature by turning screw E and regulated to time by turning wood-screw F. In either case the upper or lower screw,

independent of the other, may be turned so as to make the flat metallic bar B longer or shorter in proportion to screw or bar which supports the bob D.

The wooden bar may be protected against moisture by boiling it in oil and thoroughly seasoning and coating it with shellac, varnish, or equivalent substance.

What I claim is 1. The improved compensating clock-pendulum formed of the wooden body A, the metallic bar 13, and screw E, attached to its respective upper and lower ends, and the bob or weight D, which is supported by said screw and its attached bar and adapted to slide on the wooden part A, substantially as shown and described.

2. The combination of the screw E and bar attached thereto with the slotted wooden bar A and the weight D, having a central perforation and parallel grooves leading from its center to its lower edge, all as shown and described.

3. The combination of a wooden regulatingscrew with the divided wooden pendulum-bar, weight D, and the metallic end bar, B, and screw E, as shown and described.

4:. The combinationof the guide-bars, keepers, and wooden screw with the parts of the divided wooden pendulum-bar A, as shown and described.

JOHN NV. HILE.

Witnesses:

G. W. JOHNSTON, F. DAMOUR. 

